Writing instrument



`Fume 8, 1965 N. A. ZEPELL.

WRITING INSTRUMENT Filed Jan. 13, 1961 INVENTOR. NATHAN ALTER ZEPELL United States Patent O 1,077,724 wnrrnao msrnnrnanr Nathan Alter Zepell, Fort Madison, iowa, assigner to W. A. Sheaer Pen Company, li'ort Madison, iowa, a corporation of Delaware Filed dan. 13, 1961, Ser. No. 32,535 7 Claims. (Cl. lill-4d) This invention relates to writing instruments and has special reference to a fountain pen of the type having a retractable writing element and control means adapted to exclude air from the iluid reservoir and supply channels.

More particularly, this invention pertains to a fountain pen comprising a barrel having an open forward end, a fluid reservoir within the barrel, a writing element housed within the barrel forwardly of the reservoir section and terminating in a valved tip having a flexible writing point, an actuating unit carried by the barrel and including a manually operable portion extending outside of the barrel and engaging the internally disposed reservoir to reciprocate the writing element and thereby move the writing point through the open forward end between the exposed position and concealed position, there being a feed member communicating between the reservoir and the tip whereby when the writing point is flexed fluid is directed thereto for writing.

Irl the usual type of fountain pen, it is necessary to provide for entry of air into the reservoir to replace the fluid used during writing. Due to the difference in weight, the air rises above the writing fluid and remains thereabove regardless of the position in which the fountain pen subsequently may be held.

The air thus present in a fountain pen reservoir will expand or contract if the implement is subjected to uctuations in temperature and/ or pressure.

An increase in temperature or a decrease in barometric pressure may readily cause an undesirable condition in the usual fountain pen should it be held in a position resulting in isolation of air in the closed end of the reservoir, as while writing. Under these conditions a quantity of fluid, equal to the increase in air volume, will be forced from the reservoir and into the expansion chambers of the feed. Should the expansion chambers not be of sufficient capacity, a portion of this fluid will drip from the writing instrument into the cap or blot the writing surface or soil the users hands or clothing. lt has been observed that this is a particularly acute problem in air travel, in which great extremes of temperature and pressure may be encountered in relatively short periods of time.

Further, in the usual type of fountain pen, it is necessary to provide a cap or other means for isolating the point and feed assembly from the atmosphere to prevent evaporation of the volatile constituents of the writing fluid. As is well recognized in the art, such evaporation is particularly undesirable because of the resultant drying out and subsequent hard starting of the pen. However, the usual fountain pen cap may readily become separated from the balance of the instrument, resulting in loss or damage, whereafter it is practically impossible for the user to carry the implement without soiling his clothing.

Furthermore, in present day fountain pens the overall capacity of the reservoir is limited as a result of the above described problem of expansion of air which may be trapped above the iluid. This necessitates relatively frequent relling of the pen. And while the prior art includes a number of suggestions for means of controlling a large capacity, such as reservoir valves, capillary inserts and the like, none of these arrangements have proven commercially successful. Thus, the advantages of a ice large capacity have long been recognized, but it has not been practical to provide such a capacity prior 'to this invention.

Accordingly, it is a principal object of this invention to provide a fountain pen having a reciprocal writing element which does not require isolation from the atmosphere when in the storage or concealed position.

Another object of this invention is to provide a fountain pen which has a large fluid capacity but which is not subject to leaking or flooding as a result of temperature or barometric pressure changes.

A further object of this invention is the provision of a fountain pen in which the writing lluid is contained in a vented reservoir section having means therein between the fluid and the atmosphere and movable in response to withdrawal of fluid during writing.

A still further object of this invention is to provide a fountain pen having a writing unit assembly which seals the fluid supply channel to prevent evaporation while the implement is not in writing use.

Yet another object of this invention is the provision of a fountain pen having a writing unit assembly which is adapted for use with a replaceable fluid cartridge and which is reciprocal as a unit with such a cartridge in order to move the writing tip between concealed and writing positions while the lluid supply is sealed from the atmosphere.

Further and additional objects of this invention will be apparent from the following description when taken with the accompanying drawings, in which;

FIG. l is a broken longitudinal sectional view of a fountain pen embodying this invention and illustrating the arrangement of parts as conditioned for storage;

G. 2 is an enlarged fragmentary sectional view of the forward portion of the embodiment of FIG. 1 showing a change in position of the parts as conditioned fo writing;

FIG. 3 is an enlarged fragmentary sectional view of the forward portion of the embodiment of FIG. 1 showing the position of the parts during writing; and

FlG. 4 is an exploded view of the writing and support elements of the writing unit assembly as incorporated in the embodiment of FIG. 1.

Referring now to FIG. 1 of the drawing, the fountain pen illustrated therein includes a barrel l0 which, for convenience in manufacture and assembly, comprises a forward portion l2 and a rearward portion lilthreadedly secured in axial alignment. While various materials may be used for these barrel portions, in the illustrated embodiment the forward portion l2 preferably is molded of a plastic material having good dimensional stability and a lustrous and long wearing surface, with the outer shell or cap of the rearward portion ld being formed of a metal such as stainless steel or the like. The forward and rearward barrel portions are held in axial alignment by the threaded coupling lo which is frictionally retained adjacent the open end of the rearward barrel portion 14.

Disposed within the barrel 1li is a fluid reservoir section l ywhich may be provided in the form of a disposable cartridge as shown in the illustrated embodiment. The cartridge consists of an elongated generally cylindrical body portion 2li made of any one of a number of materials which are substantially inert to the constituents of the usual writing fluid. However, because of its toughness and resistance to breakage, a relatively resilient plastic such as polypropylene or polyethylene is preferred. At the forward end of the body portion 2l) is a closure disc 22 which may be formed asa separate piece, as illustrated, or molded integral with the body portion 2li. As will be described in more detail hereinafter, the closure disc 22 includes a centrally disposed bore 2d ex- 3 tending through an upwardly projecting collar or stop means 25.

One of the features of this invention is the prevention of any possibility of a build-up of pressure within the reservoir regardless of temperature or pressure conditions. As will be explained in more detail herebelow, this feature is accomplished by reducing the effective volume of the reservoir as fluid is drawn therefrom during writing, thereby eliminating any necessity of intermixing air and 1huid in the reservoir. As will be understood, the term effective, as used herein, refers to the volume actually displaced by fluid in the reservoir.

The rearward end of the body portion Zit is furnished with a washer 2S, having a centrally disposed aperture or vent 3ft which is in communication withthe atmosi phere through the interior of the barrel if?. As will be section 18 is a writing unit assembly 32 which is longi.

tudinally reciprocable within the bore 35 and the eccentric bore 34 which extends through the forward end of the barrel portion l2. The writing unit assembly 32 includes a writing element 33 made of a gold or other non-corrodible alloy and terminating at its forward end in a valved tip 4t?, which includes a pair of nib portions defining a flexible or displaceable writing point 4l. As can best be seen in FIG. 4, the tip 4t? includes longitudinally aligned apertures d2 and 4d. Y Extending,V between the apertures 42 and dd is a minute opening 45, and extending forwardly of the lower aperture 44 and between the nibs is a slit d3 normally which is closed except upon contact of the writing point 41 with a writing surface. To a substantial degree, the flexibility of the writing tip it? may be controlled by the thickness of the material from which the writing element 38 is fabricated, in combination with the generally arcuate shaped side cutouts 50 which are provided immediately above the writing tip.

ln order to conduct writing uid from the reservoir 1S to the valved tip 4*?, there is mounted within the writing element 3S a feed member 52 which generally may be cylindrical in configuration. The forward end of the feed member 52 preferably is reduced in diameter and provided with a transversely disposed end 54 which terminates in an outlet 56 extending into the lower aperture 44 of the valved tip 49, as can best be seen in FIGS. 2 and 3.

As previously mentioned, the fluid reservoir i8 may be provided in the form of a disposable cartridge, and for this reason, the upper end of the feed member S2 extends rearwardly beyond the writing element 5S for detachable engagement with the bore 24 of the closure disc 22. The upper end of the feed member 52 preferably is cut on a bias so as to provide a sharp cutting edge or point 5S, adapted to pierce readily the usual diaphragm or membrane as may be provided on the closure dise 22 in order to seal the bore 24. Although various other arrangements may be used in order to hold the writing element and feed member assembled, it is preferred to spin or otherwise form the rearward end of the writing element 3S inwardly to form an annular ring 6@ in an adjacent recess in the outer surface of the feed member.

One of the features of the present invention is the elimination of the necessity of using a separable cap or any other mechanism for protecting the writirrfY point or sealing the writing unit assembly from the atmosphere. This Vis accomplished by the valved tip 4Q, which includes means adapted to close the outlet S5 except when the writing point il is displaced or flexed during use. Referring particularly to FIGS. 2 and 3, there is shown a cover 62 which overlies at least a portion of the valved tip 4d; preferably, it substantially envelope the tip. While this cover member d2 may be preformed as by molding, it is preferred to apply it to the writing element by a dipping or spraying process. So as not to interfere with the displacement or flexing of the writing tip during use, the cover 62 should be relatively thin and resilient, such resiliency being provided by several well-known rubber or plastic compounds. One such compound may include latex particles dispersed in an aqueous vehicle.

As best illustrated in FIGS. 1 and 2, the outlet 56 normally lies on a plane substantially level with the upper surface of the valve tip dit. Thus, when the tip 4t) is in the normal unflexed condition, the cover means 52 will effectively seal the outlet 56 to prevent any egress of ink therefrom. Accordingly, there is communication between the outlet 56 and the forwardly extending slit 48 only during such time as the writing point 41 is flexed upwardly during writing as shown in FlG. 3.

Prior to applying the cover means 62 to the writing element 33, a plug or the like is inserted into the forward aperture 4d so that the aperture is not filled with the material of the cover 62 during the dipping or spraying process. The subsequent removal of the plug results in a slight flange of material around the underside of the aperture dit, which `flange slidably but sealably engages the outer circumference of the transverse end 54 of the feed member 52. This feature is illustrated best in FIG. 3, which clearly shows that while the penis in use, writing fluid will be confined within the forward aperture 44 and the forward slit #i3 which is surrounded by the cover means 62. Thus, the only Contact between air and ink will be at thel extreme forward end or writing point 4l of the valved tip Il@ during actual writing use of the pen.

Another feature of the cover means 62 is that it will positively prevent any transfer of fluid from the writing element 38 to the inner surface ofthe barrel 12 as defined by the bore 3d.

The top portion of the bore 34 preferably is flared outwardly from the axis of the pen to provide sutlicient room for limited flexing of the Vvalve tip 40. Or alternately, the bore 34- may be made slightly oversize with respect to the size of the writing element 38. Regardless of the particular arrangement utilized, however, the top portion of the bore 34 forms a stop against which the tip 40 may abut during writing thereby preventing too great a flow of fluid from the outlet 56. Merely as an example, the valved tip 4i) preferably is allowed to flex between 5-15 Vthousands of an inch when using an outlet on the order of 1G-l5 thousandths inside diameter. A larger or smaller outlet, of course, may require a smaller or greater amount of movement of the tip d@ in order to Secure a proper flow of fluid.

Overlying the cover means 62 is a support member which is formed of a semi-rigid plastic 0r metal. AS illustrated best in FIG. 4, the support member utilized in the embodiment is in the form of a sleeve 66, the top portion of which is provided with a plurality of slits 68 extending to the forward end of the sleeve 66. The resultant tongue portion itl will flex readily upon movement or displacement of the valved tip 4d. The rearward end of the sleeve 66 is provided with an annular head 72. The sleeve 66 is sized so as to frictionally receive the writing element 38, with the rearward end of the writing element abutting the inwardly extending portion of the annular head 72. The feed member 52, as discussed previously, extends rearwardly beyond the head 72 of the sleeve 66 for detachable engagement with the cartridge reservoir section i8.

Carried by the upper barrel portion 14 is an actuating unit which is engaged with and adapted to move the reser- Voir section 18 and writing unit assembly 32 forwardly so as to extend the writing point 41 of the tip 40 beyond the forward barrel portion l2. This actuating unit includes a manually operable portion 74 which extends outside of the barreland which also serves as a pocket clip Y in the present embodiment. An internally mounted actuating spring '76 is operatively engaged with an inwardly directed portion 75 which is provided on the dependent end of the clip portion 74, such engagement being permitted by an aperture 7S disposed in the upper barrel portion 14 adjacent the inwardly directed portion 75. As described in more detail herebelow, the actuating spring 76 is arranged for engagement with a driving member 78 which is disposed within the barrel in abutment with the uid reservoir 1S. The clip member 74 and the actuating spring 76 are secured together at the mounting portion 80, and are pivotally movable as a unit about the point S1 on the upper barrel portion 14. Thus, as will be apparent, manual movement of the forward or dependent end of the clip portion 74 inwardly toward the axis of the pen will result in movement of the inwardly directed portion 75 through the aperture 77 and conjoint movement of the actuating spring 76, thereby forcing the driving member 78 forwardly as a result of engagement of the enlarged lower end 82 of the spring member 76 with the inclined surface 84 of the driving member 78. Retraction of the reservoir section 18 and writing unit assembly 32 is then effected by manual pivotal movement of the clip member 74 and spring 76 in an outward direction.

Disposed between the outwardly extending portion of the head 72 and shoulder 86, formed by the concentric bores 34 and 36, is a resilient coil spring 8S. The purpose of the spring 83 is to urge the writing unit assembly 32 and reservoir section 18 rearwardly to the tip concealed position illustrated in FIG. l upon outward pivotal movement of the clip member 74 and actuating spring 76.

During replacement of the cartridge reservoir section 18, there will be a rearward pull on the writing unit assembly 32 as a result of frictional contact between the rearward end of the feed member 52 and the bore 24. Also, the coil spring 3S will exert a rearwardly directed force on the head 72 of the sleeve 66. Because of the possibility of abuse to the writing unit assembly 32 should it be withdrawn from the pen during removal or replacement of the cartridge reservoir, the sleeve 66 is provided with a radially extending finger 90 slidable within a groove 92 formed as an outward extension of the bore 34. A collar 94 is then threadedly engaged with the rearward end of the bore 34 to act as a means of limiting rearward movement of the finger 90. Furthermore, because of the finger 9G and groove 92, the writing unit assembly 32 is positively prevented from any undesirable axial rotation.

As outlined herebefore, the aperture 30 acts as a vent to provide communication between the atmosphere and the interior of the reservoir section so as to eliminate any possibility of an increase in pressure on the writing fluid and subsequent expulsion of such fluid from the reservoir. To prevent escape of writing fluid through the vent 36 should the pen be inverted, and evaporation of the volatile elements of the Writing duid, means is provided within the reservoir and between the vent 30 and the writing fluid. While the means may take several forms, it is shown in the instant embodiment to comprise a follower 96 which sealably but slidably engages the interior wall of the body portion 2i) of the reservoir section 18. To insure against sticking of the follower 96 within the reservoir as it descends with the level of the writing iiuid, it preferably should be of a deformable nature. Such a characteristic may be provided by forming the follower 96 of a iiaccid plastic or rubber, a viscous grease or a gelatinous material.

As the writing fluid in the reservoirV section 18 nears depletion the follower 96 will engage the upwardly extending collar 26 provided on the closure disc Z2. Collar 26 thus insures that none of the material of the follower 96 will come into contact with or enter the feed path within the feed member V52. As can readily be understood, the feed member 52 must be maintained free of any foreign material which might interfere with the proper ow of uid during use of the fountain pen- When the forward surface of the follower 96 reaches the rearward edge of the collar 26, it may trap a small quantitiy of writing uid in the annular space between the outer surface of the collar 26 and the inner surface of the body portion 2,11. And in order to use at least a part of this trapped fluid, there is provided one or more capillary fissures 98 communicating between the annular space and the bore 24.

To condition the herein described embodiment for writing, the only action required on the users part is a mere inward movement of the lower end of the clip member '74 through aperture 77. Such inward movement results in corresponding inward movement of the lower end S2 of the actuating spring 76, and subsequent forward movement of the driving member 73. As the driving member 7S moves in a forwardly direction, the reservoir section 13 and writing unit assembly 32 are urged forwardly against the action of the coil spring 88 until the writing point 41 is positioned slightly beyond the lower barrel portion 12. In this position, the writing point 41 may then be pressed against paper or a similar writing surfa and displaced upwardly relative to the outlet 56 of the feed member 52. Capillary attraction between the writing point 41 and the writing surface will then draw fluid from the reservoir section 1S through the feed member 52 and slit 48.

The above described withdrawal of uid will cause forward movement of the follower 96 Within the reservoir 18 thus reducing the effective volume thereof, until the uid is completely exhausted. Such for-ward movement of the follower 96, of course, requires the entry of air into the reservoir rearwardly of the follower through the above described air pathway consisting of the interior of the barrel 1i?, and the vent passage 3?, which are connected by the channel 1d@ provided on the forward end of the driving member 78.

The fit between the writing unit assembly 32 and the bore 34 is relatively loose and the space thus provided will allow movement of air between the interior of the barrel and the atmosphere. However, upon extension and retraction of the fluid reservoir 1d, the movement of air will be quite rapid and to facilitate this air movement, there is provided an aperture 104 extending from the bore 36 radially through the barrel portion 12.

As mentioned hereinabove, writing fluid within the reservoir section 1S is completely protected against any contact with air except at the writing point 41 during use of the pen. Thus, when outlet S6 is closed during nonwriting, and regardless of whether or not the writing element 37 is in the retracted or extended position, there will be no evaporation of fluid from the reservoir or feed channels, and only the slight amount remaining at the point 41 will be subject to contact with air. However, the very minute amount of dried coloring material which may be left at the point d1 will be suthcient to interfere with subsequent dow of ink, particularly since such dried material will be redissolved and washed away quickly.

Although the follower 96 will move forwardly within the reservoir as fluid is withdrawn during writing, it will be understood by those in the art that no rearward movement of the follower 96 will occur should the implement be inverted. This feature is provided by the slight amount of friction or adhesion which is present between the follower 96 and the interior wall of the body portion 2t?, and further by the effective sealing of the outlet 56 whereby no air is permitted to enter the feed member S2 or reservoir 18.

Upon depletion of the fluid supply in the reservoir section 13 the upper barrel portion 14 may be disengaged from the lower barrel portion 12, and the empty reservoir section removed and replaced by a fresh cartridge. During such time as the barrel portions may be disassembled, the driving member 78 will be retained within the upper barrel portion 14 by means of the shoulder 102 formed by the upper edge of the coupling 16.

It is understood that although only one embodiment is illustrated and described herein, the invention is not to be limited thereto as many modifications may be made without departing from the true spirit and scope of this invention. Accordingly, this invention is not to be limited to the embodiment described above and it is contemplated, by the appended claims, to cover any such modications which fall within its true spirit and scope.

I claim:

1.. A writing instrument comprising a barrel having an open forward end, a reservoir section within said barrel, said reservoir section comprising a fluid cartridge having a vent passage for communication with the atmosphere,

a writing element extending forwardly of said reservoir section, said writing element being provided on its forward end with a longitudinal slit to define resilient nibs forming a flexible writing point, and an aperture in communication with said slit, a feed member adapted for communication with said cartridge and providing an outlet disposed in said aperture intermediate the ends of said slit, a thin layer of resilient material bonded to Iand substantially enveloping said writing point for sealingly engaging said outlet and being disengaged therefrom when said nibs are dexed during writing, and means in said cartridge for restraining said liuid against movement through c# a pair of resilient nibs defining a fluid path therebetween, said writing element including an aperture communicating with the rearward end of said uid path, a generally cylindrical feed member communicating with said reservoir section, said feed member being mounted within said Writing element and having a transverse portion providing an outlet disposed within said aperture, and resilient means v substantially enveloping said nibs and normally engaging said vent, said means being movable to reduce the volume of said cartridge in response to withdrawal of duid through said writing point.

2. A writing instrument comprising a barrel having an open forward end, a reservoir section within said barrel, said reservoir section comprising a duid cartridge removably received within said barrel and including a vent passage for communication with the atmosphere, a writing element extending forwardly of said reservoir section, said writing element being provided on its forward end with a longitudinal slit to define a pair of resilient nibs forming a flexible writing point and an aperture in communication with said slit, a feed member detachably connected to said cartridge and providing an outlet disposed within said aperture, a thin layer` of resilient material substantially enveloping said nibs for sealingly engaging said outlet and being disengaged therefrom when said nibs are displaced, said resilientrneans sealingly engaging said nibs along said slit to confine said fluid to said slit as it is withdrawn during writing, and means in said cartridge for restraining said duid against movement through said vent passage, said means being movable to reduce the volume of said cartridge in response to withdrawal of fluid through said slit.

3. A writing instrument comprising a barrel having an open forward end, a fluid cartridge removably received within said barrel, said cartridge including a vent'passage for communication with the atmosphere, a writing element extending forwardly of said cartridge, said writing element being provided on its forward end with a longitudinal slit to define a pair of resilient nibs forming a flexible writing point and an aperture in communication with said slit, a feed member detachably engaging said cartridge and providing an outlet disposed intermediate the ends of said slit, a thin layer of resilient material substantially enveloping said nibs for sealingly engaging said outlet in the absence of tiexure in said nibs, said means being disengaged from said outlet to permit movement of fluid therethrough only when said nibs are flexed, SaidV resilient means sealingly engaging said nibs along said slit to confine said fluid to said slit as it is withdrawn during writing, a resilient support member overlying said resilient means, and means in said cartridge for restraining said fluid against movement through said vent, said means being movable to reducethe volume of said cartridge in response to withdrawal of uid through said slit.

4. A writing unit assembly for a fountain pen of the type having a barrel and a fluid reservoir Section adapted to contain a supply of writing fluid within said barrel,

comprising a generally cylindrical writing element extend-` ing forwardly of said reservoir section and terminating in said transverse portion for sealing said outlet and being disengaged from said portion to permit fluid movement through said outlet when said nibs are displaced.

5. A writing instrument comprising a barrel having an open forward end, a fluid reservoir within said barrel, a writing element extending forwardly of said reservoir section and terminating in a flexible writing tip and an aperture in communication with said slit, a stop provided by said barrel for limiting the ilexure of vsaid writing tip, a feed member communicating with said reservoir section and providing an outlet disposed adjacent said tip, and means consisting of a thin layer of resilient material bonded to and substantially enveloping said writing element Yproviding a barrier against fluid .transfer between said writing tip and said stop.

6. A writing unit assembly for a fountain pen of the type having a barrel and a fluid reservoir section adapted to contain a supply Vof writing fluid within said barrel, comprising a writing element extending forwardly of said reservoir section and terminating in a pair of resilient nibs defining a fluid path therebetween, said writing element including an aperture communicating with the rearward end of said fluid path, a feed member communicating with said reservoir section, said feed member being mounted within said writing element and having a transversek portion providing an outlet disposed within said aperture, and resilient means substantially enveloping said nibs and normally engaging said transverse portion for sealing said outlet and being disengaged from said portion to permit fluid movement through said outlet when said nibs are displaced.

7. A writing unit assembly for a fountain pen having a uid reservoir, said assembly `comprising a writing element extending forwardly of said reservoir and terminating in a pair of displaceable nibs defining a fluid path therebetween, said writing element having an aperture communicating with said duid path, a feed member communicating with said reservoir and having a portion extending from one side of said writing element and providing an outlet disposed within said aperture, and resilient means aixed to the opposite side of said writing element and at least partially covering the aperture, said resilient means being positioned to engage and seal said outlet and being disengageable from said outlet to permit the ow of fluid therethrough and into said aperture and fluid path only when said nibs are displaced.

References Cited by the Examiner UNITED STATES PATENTS 207,399 8/ 78 Dieckmann et al 120-48 552,679 l/96 Veit 120-48 849,513 4/07 Sturm 120-42 912,659 2/09 Faust 120-45.6 X 928,312 7/09 Lloyd 120-48 1,145,472 7/15 Durand 120-42 1,775,068 9/30 Debenedetti 1Z0-42.03 2,416,112 2/47 hfoore 1Z0-42.03 2,479,414 8/ 49 Sanbonmatsu 1Z0-42.03 2,495,013 1/50 Martin 1Z0-42.4 X 2,669,970 2/54 Gordon 120-51 2,883,969 4/59 Sams 129-424 2,949,887 8/60 Martin et al 120-42.03 2,988,055 6/61 Platt 1Z0-42.03

JEROME SCHNALL, Primary Examiner.

GEORG-E NINAS, JR., JOSEPH D. BEIN, Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No. 3, 187, 724 June 8, lgf

Nathan Alter Zepell Column 3, lines 22 and 23, for "eccentric" read concentric column 6, line 47, for "37" read 38 Signed and sealed this 14th day of December 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

6. A WRITING UNIT ASSEMBLY FOR A FOUNTAIN PEN OF THE TYPE HAVING A BARREL AND A FLUID RESERVOIR SECTION ADAPTED TO CONTAIN A SUPPLY OF WRITING FLUID WITHIN SAID BARREL, COMPRISING A WRITING ELEMENT EXTENDING FORWARDLY OF SAID RESERVOIR SECTION AND TERMINATING IN A PAIR OF RESILIENT NIBS DEFINING A FLUID PATH THEREBETWEEN, SAID WRITING ELEMENT INCLUDING AN APERTURE COMMUNICATING WITH THE REARWARD END OF SAID FLUID PATH, A FEED MEMBER COMMUNICATING WITH SAID RESERVOIR SECTION, SAID FEED MEMBER BEING MOUNTED WITHIN SAID WRITING ELEMENT AND HAVING A TRANSVERSE PORTION PROVIDING AN OUTLET DISPOSED WITHIN SAID APERTURE, AND RESILIENTLY MEANS SUBSTANTIALLY ENVELOPING SAID NIBS AND NORMALLY ENGAGING SAID TRANSVERSE PORTION FOR SEALING AND OUTLET AND BEING DISENGAGED FROM SAID PORTION TO PERMIT FLUID MOVEMENT THROUGH SAID OUTLET WHEN SAID NIBS ARE DISPLACED. 